Thermometer



' Dec, 31, 1929. H. Y. NORWOOD THERMOMETER Filed Jan. 26, 1928 INVENTORy. M BY ,0; ATTORNEY Patented Dec. 31,1929 r 1,741,330

was STATES PATENT" OFFICE HARRY Y. nonwoon, OF WEST nusn, NEW YORK,ASSIGNOB TO 'rAYn-oa nsrnu unnr COMPANIES, OF ROCHESTER, new YORK, ACORPORATION or NEW YORK zrnnnmomn'rnn Application filed January 26,1928. .Serial .No. 249,575."-

This invention relates to thermometers of ,for carrying out the objectof the invention; the type having a colored stripe in the back Fig. 2 isan end view' thereof;

of the mercury column to make the position 3 is an enlargedcross-section taken of the top of the column more easily visible, on lne 3-3, Fig. 1; a i/e. to facilitate the-reading of the .ther--' Fig; 4is 'a similar cross-section showing 55 mometer. a subsequentstage in theexecution of the 111- Heretofore, it was found difficult to obtainvcntion; and I a suitable color contrast, principally for the ,Fig. 5 isan enlarged cross-section of the reason that is was difficult, ifnot'practically finished tubing.

, impossible to obtain a sufiicient depth of color My inventibn, brieflyexpressed, consists in 60 or chroma ota desired hue and color value.applying to the body of glass, after the latter In the manufacture ofglass tubing emhas been rolled asabove described, two relbodyinglens-fronts and colored stripes, it has atively heavy-layers of enamelor the. like been found desirable to dimension and posiseparated fromeach-other by a narrow gap 65 tion' the stripes so as to assume in thefinished and then filling a colored enamel into the product avisuallwidth equal to that ofthe gap to fillit up. w I bore andthecolumn of mercury therein. Ac- Havlng reference to the drawings, 1repcording tothe usual practice,a mass of molten resents, a blow plpeand 2 a mass of. glass glass is gathered on a blow pipe and afterthereon. A templet 3 isflplaced upon the 70 air is blown into it, themass of glass is g as 1 PVQ a u a e P01431011 e 9fshaped by turning thepipe and by rolling of Then a suitable enamel 4, preferably white thebody of glass on a plane surface to give enamels 1S pp b th's q pit acircular cross-section and to symmetrilet so as to form relativelythicklayers, prefcally dispose the air bubble. Then an enamel erablyncreasing in thickness from the out- 7F of the desired color, say red,in the formof a Ide toward the templet, In m nner I narrow layer ofplastic material, is laid upon H111 abl f I'In a heavyfor thicklayerwith the mass of glass, whereupon some more a relatlyely p g e1;n 5h'e'cr- Af er v clear glass is gathered around it. In some the Whlte enamel Spp 1 d5: h instances a layer of white enamel is supertemplet and fill hFQ S-EQiQ T P left Wlth posed upon the colored enamel to extend to the cd enamel h m o enamel 8 oth sides thereof, before the additional clearcan h q y PP f* t whlte glass is gatheredaround it. In any case, theenamel can 'Wh ehamel thus layer of colored enamel has a tendency toholds t Colored enamel'ln place and preflow or 'spr'eadlaterally andthereby decrease h from P h laterally om m r in thickness. Infact, theenamel is usuall mlly d r asmg in depth; I have found applied by a sptula or the like so that the that y PP SY red 1 of a p hue depth Of-thelayer is bound to be small; ,-As n @0101 Value, I Ohtflm a much m remien? the result of this inherent limitation as to Siva dePth of colorchroma than W3 P depth of thelayer the colorin the finished sible 7 hthe u m article usually appears light and faded. .After the coloredenamel 5 e My invention has for its obj ect to provide. Eggs i g f ofglass 15 gathered 1 I y of glass 2 whereupon the v a method of makmgglass tubmg whereby It same is subjected to a lensing operation which ispossible t6 give thecolor-ed stripe richer. determines the final shapeof the glass for 45 deeper hh m c h was heretoiom P drawing, asindicated in Fig. 5. wherein the sible.

For aifull explanation of'the invention and iflg fig gflgg gg gd ssuriace n its Pmctieal Sighifi'cahce, Referenceismflde By the methoddescribed,,itfis made posto the accompanying drawings, wherein: sible toprovide 'a layer otena'mel of much I 5 Fig. I is an elevation ofapparatus suitable greater thickness than wasfpossible; with the 21,741,380 51d methods and the hem; of the colored enamel, due to theincreased thi .of the layer is correspondingly deeper and richer.

' I c aim: a LIn' a process of inakin glass tubing hav- I ing a coloredstripe back-'0 t e bore, the steps which'con'sist in covering; surfaceportion of a ball of glass while in Plastic condition depositingvitreous materi'a I on both sides of 1 and up to thecovered portion toform two .layers then uncovering said covered portion and" iillingi theuncovered portion with a" .-colored'vitreous'material; S 2; In a processof makinjfg' tubing havii1g a; colored stripe back 0 t. chew, the stepswh ch consist in coverin a, surface portion f of a ball of glass while1n plastic cdndition, depositing vitreous material on. both sides of thecovered portion to form layers increasing in thi ckness toward thecovered portion then uncovering the covered portion and filling thespace left between the" layers with a colored vitreousmaterial. f o Intestimony whereof I aflix'mfisignature.

, HARRY n NO WOOD.

